Surface Drainage Issues FAQ

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Building a city drainage system that guarantees protection against flooding requires participation from property owners and the City of Edmonton. Many homes and commercial areas were built prior to the development in 1993 of city-wide surface drainage plans and procedures.

Homeowners need to look at their own lot grading, and take the necessary steps to prevent flooding and property damage. They should also try to avoid any disputes with neighbours over lot grading and surface drainage issues.

When a City of Edmonton Lot Grading Inspector completes a Rough or Final Grade Inspection and issues an approval, it verifies that at the time of inspection the property was in compliance with the Drainage Bylaw. From that moment on, as the owner of the property, it is your obligation to maintain the lot grading in perpetuity regardless of natural settlement or activity caused by yourself or damage by a 3rd party. Property owners are required to ensure that others do not trespass and damage grading on your private property. The City of Edmonton is unable to enforce or police such actions or determine cause or fault. That would require a civil action suit against the offending party or you as the owner should consult with the offending party and advise of the damage. You may also wish to consult with the Builder's Warranty program if damage by a 3rd party is covered.

Examine your own grading and be prepared to make changes to ensure that your foundation grading will direct surface drainage away from your house. Evaluate the existing drainage pattern and discharge locations with your neighbour to determine the best point of discharge for downspouts or sump discharge hoses. Discharge points must not be less than 15 centimetres from the property line.

A swale is a shallow, sloped channel that conveys water from the buildings towards the street or lane. Lot grading between the houses has to be maintained for a positive and consistent slope along drainage swale.

All property owners are responsible to grade their lots properly to allow lot grading / surface drainage away from buildings and towards the public right-of-way.

Many houses in older areas have the downspouts connected to the storm sewer system inside the house. Basement flooding may occur during heavy rainstorms when the storm sewer system is flowing at peak capacity, causing the sewer back-up.

Disconnecting the downspouts from the storm system allows the roof drainage to flow onto the ground before reaching the catchbasin in the street. The City of Edmonton supports this disconnection if lot grading / surface drainage does not impact adjacent property or environmentally sensitive locations. In many cases, improvement of the existing lot grading is required to ensure the compliance with the Drainage Bylaw

Examine your own grading and be prepared to make changes to ensure that your foundation grading will direct surface drainage away from your house. Evaluate the existing drainage pattern and discharge locations with your neighbour to determine the best point of discharge for the downspouts. Discharge points must be at least 15 centimetres away from the property line.

A swale is a shallow, sloped channel that conveys water from the buildings towards the street or lane. Lot grading between the houses has to be maintained for a positive and consistent slope along drainage swale. A shared swale on the common property line is the ideal case. However, a separate (internal) swale within the lot is sometimes required to solve a lot grading problem.

There is no surface drainage design for properties developed prior to 1989. However, the Alberta Building Code and the Drainage Bylaw provide requirements for all houses to have a 10% slope away from the foundation walls.

In the case of infill housing, the owner must submit a Lot Grading Plan to the City of Edmonton for review and approval prior to the Development and Building Permit being issued.

For more information on City of Edmonton Infill please refer to the following:

After construction and lot grading is completed the owner must submit a Lot Grading Certificate for to the City of Edmonton followed by a lot grading inspection to ensure compliance under provisions of the Drainage Bylaw and the lot grading guidelines.

To avoid surface drainage problems, you should:

review and repair your foundation grading to re-establish the slope away from your house

ensure that you have downspout extensions or splash pads to convey surface water at least 2 metres away from the house and at least 15 cm away from adjacent property

consult with the adjacent property owner to create a drainage plan that works for both properties

check lot grading between the houses to make sure a positive and consistent slope along the drainage swale has been maintained

For Investigations and Enforcement of the Drainage Bylaw you must contact the City of Edmonton at 311.

If your neighbour has re-landscaped his foundation grading to provide the required slope of 10% away from his house without changing the existing grade at the property line, then you should examine your own lot grading and be prepared to make changes to ensure that your foundation grading is sloped away from your house. If you have poor or negative grade, surface water will flow towards your foundation wall and increase the risk of basement flooding. Evaluate the existing drainage patterns and discuss with your neighbour to overcome common drainage issues.

If the re-grading has resulted in directing surface drainage from the neighbour’s roof or foundation directly onto your property, there may be a bylaw violation.

The City of Edmonton recommends maintaining positive slope from your foundation walls and paying close attention to how your stormwater is managed and directed.

You may want to call 311 and request to speak with a City of Edmonton Lot Grading Inspector. When provided with your address we can guide you with the appropriate requirements and make you aware of any specific designs that must be maintained. The owner is responsible to establish and maintain lot grading under provisions of the Drainage Bylaw.

Ask your neighbour to consider repairing his foundation grading in concern with your re-grading efforts. The combined foundation grading of both houses will form a common property swale that will convey damaging surface drainage away from both buildings. Grading changes to only one house will likely direct surface drainage towards the adjacent building. This is not permitted.

When working independently, you must ensure that lot grading from the slope that you create away from your house is directed to drain towards a City of Edmonton right-of-way. You may need to construct an internal swale to achieve this requirement.

There is no permit requirement for re-grading that does not alter an existing drainage pattern. Your re-landscaping efforts must ensure that any grade changes will serve to direct surface drainage towards a public right-of-way (usually a street or a lane) without draining onto an adjacent private property. However, if there is an approved Lot Grading Plan for the area and alterations result in a complaint to the City of Edmonton, a re-application for Final Lot Grading Approval may be required. The owner is responsible to establish and maintain lot grading under provisions of the Drainage Bylaw.

Effective side-lot drainage requires the cooperation of both property owners. Check your own lot grading. All property owners are responsible to have the lot graded to direct surface water away from buildings and towards the public right-of-way. Lot grading changes that promote the flow of surface drainage from the roof or the foundation directly onto adjacent private property may be a bylaw violation. Consult with your neighbour over common drainage issues.

If you are a lawyer or a realtor working on behalf of a vendor or purchaser, we can provide that information under the Freedom of Information and Privacy (FOIP) Act. Provide a written request, including property address and legal description, to City of Edmonton Development Services, Lot Grading and we will generally respond within 2 working days.

When selling or purchasing a home, it is the owner’s responsibility to ensure that lot grading meets approval and is in compliance with the Drainage Bylaw. City of Edmonton Development Services, Lot Grading will only release this information upon receiving a written request from a registered owner or law or realty firm. This information is collected under the Freedom of Information and Privacy (FOIP) Act, and used only to maintain business practices for lot grading purposes.

All new commercial and multi-family properties have on-site stormwater management. The parking lot is designed to store rain water on the surface, which will slowly drain into the storm system through a reducer in the catchbasin. This is intended to prevent surcharging the storm sewers. All commercial and multi-family properties must contain surface drainage within the property (on-site). For More information please contact EPCOR Drainage Services, Water and Sewer Servicing at 780-496-5444 or e-mail to wass.drainage@epcor.com

All new commercial and multi-family properties are required to have on-site stormwater management. A lot grading plan indicating the proposed on-site drainage must be provided and graded in accordance with the lot grading plan and Lot Grading Guidelines. The builder of the new development must control the site grading, and stormwater management. Retaining walls may be needed to achieve this.

Adjustments to the site grading may be required to provide a better level of protection from rainfall and snow melt. For more information on City of Edmonton Lot Grading Plan requirements call 780-496-5576 or e-mail to City of Edmonton lot.grading@edmonton.ca

For More information on Stormwater Management please contact EPCOR Drainage Services, Water and Sewer Servicing at 780-496-5444 or e-mail to wass.drainage@epcor.com

Maintaining the site grading is the responsibility of the Condominium Association. If the project was built after 1993, there should have an approved lot grading plan. This plan can serve as the basis for solving surface drainage issues. Problems in projects constructed before 1993 must be solved using common sense, good grading principles, and the provisions of the Drainage Bylaw with the City of Edmonton Lot Grading Guidelines.

The Condo Board or Management company may want to call 311 and request to speak with a City of Edmonton Lot Grading Inspector. When provided with your address we can guide you with the appropriate requirements and make you aware of any specific designs that must be maintained.